/Engine/Source/Runtime/Messaging/Public/IMessageBus.h
Subscribe
virtual void Unsubscribe ( const [TSharedRef](API\Runtime\Core\Templates\TSharedRef)< [IMessageReceiver](API\Runtime\Messaging\IMessageReceiver), ESPMode::ThreadSafe > & Subscriber, const [FName](API\Runtime\Core\UObject\FName) & MessageType )